Conventionally, it is reported that when an immiscible polymer blend system is simply mechanically mixed using a normal kneading extruder (rotation speed of a screw is about 300 rpm), a theoretical and experimental limit of dispersed phase size of one of polymer components is 350 nanometers (nm) (see non-patent document 1).
Therefore, to muster performance or function of a desired polymer blend as a synergistic effect, a kneading operation is carried out using a compatibilizer having compatibility or adherence property with respect to one or both of blend components.
However, since they do not substantially dissolve in each other at the molecular level, if one of the polymer components is formed into a matrix, only a polymer blend extrudate in which a dispersed phase size of the other polymer component is several microns to submicronmeters level is obtained, and it is not possible to enhance the performance or function thereof to the limit.
A reactive processing technique which was developed 30 years ago is a method for lowering an interfacial tension to reduce a dispersed phase size by making functional groups existing between blend components react with each other (see non-patent document 1). A dispersed phase size of a polymer blend system was successfully reduced to a level of submicron meter to several tens of nanometer, but since reactive groups do not exists between the two components, this method is not realized and this fact becomes an impediment technically.
Therefore, to muster a synergistic effect of performance and function of the immiscible polymer blend system to make a blend, it is necessary to control dispersed phase in a size close to a molecular level, and it is difficult to easily produce a nanodisperse polymer blend according to an extension of the conventional technique.
A reaction product generated by a mix of additive such as a compatibilizer or a reactive processing method becomes “defect or foreign matter” in terms of structure in optical material and electronic or electric material which requires a continuous and pure microstructure, there is a drawback that the residue becomes a serious failure in effect.
Under such a technical background, the present inventors successfully produced a high shearing and forming apparatus having an inner feedback type screw capable of rotating the screw at 1000 rpm or higher (maximum output was 3000 rpm), and a patent application was already filed (see patent document 1).